Interest in analyzing small samples of biomolecules has increased the demand for microfluidic systems providing sensitive through-put analysis. Electrospray tips have proven to be a useful component in certain microfluidic analytical systems. For example, see Bousse et al., U.S. Pat. No. 6,803,568 (application Ser. No. 10/649,350), “Multi-channel Microfluidic Chip for Electrospray Ionization,” providing a high performance electrospray ionization device for mass spectrometry applications, and Stults et al., application Ser. No. 10/681,742, “Methods and Apparatus for Self-Optimization of Electrospray Ionization Devices,” which are incorporated herein by reference.
In light of the burgeoning fields of proteomics, genomics and pharmacogenetics, and their diagnostic applications, there is a need for microfluidic analysis systems with durable, low-cost, easily-manufacturable, and readily-reproducible components, including electrospray tips. Thus, there remains a need for even more improved electrospray tips, along with improved methods of making them.